Quoting ts <decoux / moulon.inra.fr>: 
>  
>     if (rb_block_given_p()) { 
>         proc = rb_block_proc(); 
>     } 
>  
>  when you want to call it 
>  
>     rb_funcall(proc, rb_intern("call"), ...); 
 
Ah nice! That is what I wanted. Thanks a lot. 
  
>  don't forget to define a mark function, and call rb_gc_mark(proc) 
 
You mean a mark function for the Ruby garbage collector? 
 
Regards, 
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